Kelvin is a unit of measurement used to express temperature. It is named after William Thomson, also known as Lord
Kelvin, who was a famous Scottish physicist. The
Kelvin scale starts at absolute zero, which is the point where all molecular motion ceases. In this scale, zero
kelvin (0 K) represents the coldest possible temperature. Unlike Celsius or Fahrenheit, the
kelvin scale does not use negative numbers.
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